An intraluminary prosthesis is a medical device used in the treatment of diseased bodily lumens. One type of intraluminary prosthesis used in the repair and/or treatment of diseases in various body lumens is a stent. A stent is generally a longitudinal tubular device formed of biocompatible material, which is useful to open and support various lumens in the body. For example, stents may be used in bodily vessels, such as in the coronary or peripheral vasculature, esophagus, trachea, bronchi colon, biliary tract, urinary tract, prostate, brain, as well as in a variety of other applications in the body. These devices are implanted within the vessel to open and/or reinforce collapsing or partially occluded sections of the lumen. While stents and other intraluminary prosthesis are foreign objects to the human body, they are designed to remain within a body lumen for prolonged periods or even indefinitely.
Stents generally include an open flexible configuration. This configuration allows the stent to be inserted through curved vessels. Furthermore, this configuration allows the stent to be configured in a radially compressed state for intraluminary catheter implantation. Once properly positioned adjacent the damaged vessel, the stent is radially expanded so as to support and reinforce the vessel. Radial expansion of the stent may be accomplished by inflation of a balloon attached to the catheter or the stent may be of the self-expanding variety which will radially expand once deployed. Tubular shaped structures, which have been used as intraluminary vascular stents, have included helically wound coils which may have undulations or zigzags therein, slotted stents, ring stents, braided stents and open mesh wire/filament stents, to name a few. Super-elastic materials and metallic shape memory materials have also been used to form stents.
On occasion there is a need to retrieve or reposition a stent previously deployed in a body lumen. For example, a stent may require repositioning if incorrectly located during deployment, or if it migrates after deployment. Also, the need to retrieve or remove a deployed stent may arise from a post-deployment determination that the stent was not the appropriate size for the application, or from a procedure that calls for only temporary use of the stent.
One known approach to removing a previously deployed stent or other prosthesis involves capturing a proximal end of the object with biopsy forceps or other snare, then pulling proximally to withdraw the object. One problem with this approach is that pulling or pushing a fully radially expanded stent through a body lumen can damage surrounding tissue and the stent itself.
Therefore, there is a need for a reliable and effective apparatus, system and method for removing, adjusting and/or repositioning an intraluminary prosthesis that has already been deployed, which overcomes the shortcomings set forth above while also having application to other select intraluminary objects.